drivers/mtd/mtdpart.c

   1 /*
   2  * Simple MTD partitioning layer
   3  *
   4  * Copyright © 2000 Nicolas Pitre <nico@fluxnic.net>
   5  * Copyright © 2002 Thomas Gleixner <gleixner@linutronix.de>
   6  * Copyright © 2000-2010 David Woodhouse <dwmw2@infradead.org>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  21  *
  22  */
  23
  24 #include <linux/module.h>
  25 #include <linux/types.h>
  26 #include <linux/kernel.h>
  27 #include <linux/slab.h>
  28 #include <linux/list.h>
  29 #include <linux/kmod.h>
  30 #include <linux/mtd/mtd.h>
  31 #include <linux/mtd/partitions.h>
  32 #include <linux/err.h>
  33 #include <linux/kconfig.h>
  34
  35 #include "mtdcore.h"
  36
  37 /* Our partition linked list */
  38 static LIST_HEAD(mtd_partitions);
  39 static DEFINE_MUTEX(mtd_partitions_mutex);
  40
  41 /* Our partition node structure */
  42 struct mtd_part {
  43         struct mtd_info mtd;
  44         struct mtd_info *master;
  45         uint64_t offset;
  46         struct list_head list;
  47 };
  48
  49 /*
  50  * Given a pointer to the MTD object in the mtd_part structure, we can retrieve
  51  * the pointer to that structure.
  52  */
  53 static inline struct mtd_part *mtd_to_part(const struct mtd_info *mtd)
  54 {
  55         return container_of(mtd, struct mtd_part, mtd);
  56 }
  57
  58
  59 /*
  60  * MTD methods which simply translate the effective address and pass through
  61  * to the _real_ device.
  62  */
  63
  64 static int part_read(struct mtd_info *mtd, loff_t from, size_t len,
  65                 size_t *retlen, u_char *buf)
  66 {
  67         struct mtd_part *part = mtd_to_part(mtd);
  68         struct mtd_ecc_stats stats;
  69         int res;
  70
  71         stats = part->master->ecc_stats;
  72         res = part->master->_read(part->master, from + part->offset, len,
  73                                   retlen, buf);
  74         if (unlikely(mtd_is_eccerr(res)))
  75                 mtd->ecc_stats.failed +=
  76                         part->master->ecc_stats.failed - stats.failed;
  77         else
  78                 mtd->ecc_stats.corrected +=
  79                         part->master->ecc_stats.corrected - stats.corrected;
  80         return res;
  81 }
  82
  83 static int part_point(struct mtd_info *mtd, loff_t from, size_t len,
  84                 size_t *retlen, void **virt, resource_size_t *phys)
  85 {
  86         struct mtd_part *part = mtd_to_part(mtd);
  87
  88         return part->master->_point(part->master, from + part->offset, len,
  89                                     retlen, virt, phys);
  90 }
  91
  92 static int part_unpoint(struct mtd_info *mtd, loff_t from, size_t len)
  93 {
  94         struct mtd_part *part = mtd_to_part(mtd);
  95
  96         return part->master->_unpoint(part->master, from + part->offset, len);
  97 }
  98
  99 static unsigned long part_get_unmapped_area(struct mtd_info *mtd,
 100                                             unsigned long len,
 101                                             unsigned long offset,
 102                                             unsigned long flags)
 103 {
 104         struct mtd_part *part = mtd_to_part(mtd);
 105
 106         offset += part->offset;
 107         return part->master->_get_unmapped_area(part->master, len, offset,
 108                                                 flags);
 109 }
 110
 111 static int part_read_oob(struct mtd_info *mtd, loff_t from,
 112                 struct mtd_oob_ops *ops)
 113 {
 114         struct mtd_part *part = mtd_to_part(mtd);
 115         int res;
 116
 117         if (from >= mtd->size)
 118                 return -EINVAL;
 119         if (ops->datbuf && from + ops->len > mtd->size)
 120                 return -EINVAL;
 121
 122         /*
 123          * If OOB is also requested, make sure that we do not read past the end
 124          * of this partition.
 125          */
 126         if (ops->oobbuf) {
 127                 size_t len, pages;
 128
 129                 len = mtd_oobavail(mtd, ops);
 130                 pages = mtd_div_by_ws(mtd->size, mtd);
 131                 pages -= mtd_div_by_ws(from, mtd);
 132                 if (ops->ooboffs + ops->ooblen > pages * len)
 133                         return -EINVAL;
 134         }
 135
 136         res = part->master->_read_oob(part->master, from + part->offset, ops);
 137         if (unlikely(res)) {
 138                 if (mtd_is_bitflip(res))
 139                         mtd->ecc_stats.corrected++;
 140                 if (mtd_is_eccerr(res))
 141                         mtd->ecc_stats.failed++;
 142         }
 143         return res;
 144 }
 145
 146 static int part_read_user_prot_reg(struct mtd_info *mtd, loff_t from,
 147                 size_t len, size_t *retlen, u_char *buf)
 148 {
 149         struct mtd_part *part = mtd_to_part(mtd);
 150         return part->master->_read_user_prot_reg(part->master, from, len,
 151                                                  retlen, buf);
 152 }
 153
 154 static int part_get_user_prot_info(struct mtd_info *mtd, size_t len,
 155                                    size_t *retlen, struct otp_info *buf)
 156 {
 157         struct mtd_part *part = mtd_to_part(mtd);
 158         return part->master->_get_user_prot_info(part->master, len, retlen,
 159                                                  buf);
 160 }
 161
 162 static int part_read_fact_prot_reg(struct mtd_info *mtd, loff_t from,
 163                 size_t len, size_t *retlen, u_char *buf)
 164 {
 165         struct mtd_part *part = mtd_to_part(mtd);
 166         return part->master->_read_fact_prot_reg(part->master, from, len,
 167                                                  retlen, buf);
 168 }
 169
 170 static int part_get_fact_prot_info(struct mtd_info *mtd, size_t len,
 171                                    size_t *retlen, struct otp_info *buf)
 172 {
 173         struct mtd_part *part = mtd_to_part(mtd);
 174         return part->master->_get_fact_prot_info(part->master, len, retlen,
 175                                                  buf);
 176 }
 177
 178 static int part_write(struct mtd_info *mtd, loff_t to, size_t len,
 179                 size_t *retlen, const u_char *buf)
 180 {
 181         struct mtd_part *part = mtd_to_part(mtd);
 182         return part->master->_write(part->master, to + part->offset, len,
 183                                     retlen, buf);
 184 }
 185
 186 static int part_panic_write(struct mtd_info *mtd, loff_t to, size_t len,
 187                 size_t *retlen, const u_char *buf)
 188 {
 189         struct mtd_part *part = mtd_to_part(mtd);
 190         return part->master->_panic_write(part->master, to + part->offset, len,
 191                                           retlen, buf);
 192 }
 193
 194 static int part_write_oob(struct mtd_info *mtd, loff_t to,
 195                 struct mtd_oob_ops *ops)
 196 {
 197         struct mtd_part *part = mtd_to_part(mtd);
 198
 199         if (to >= mtd->size)
 200                 return -EINVAL;
 201         if (ops->datbuf && to + ops->len > mtd->size)
 202                 return -EINVAL;
 203         return part->master->_write_oob(part->master, to + part->offset, ops);
 204 }
 205
 206 static int part_write_user_prot_reg(struct mtd_info *mtd, loff_t from,
 207                 size_t len, size_t *retlen, u_char *buf)
 208 {
 209         struct mtd_part *part = mtd_to_part(mtd);
 210         return part->master->_write_user_prot_reg(part->master, from, len,
 211                                                   retlen, buf);
 212 }
 213
 214 static int part_lock_user_prot_reg(struct mtd_info *mtd, loff_t from,
 215                 size_t len)
 216 {
 217         struct mtd_part *part = mtd_to_part(mtd);
 218         return part->master->_lock_user_prot_reg(part->master, from, len);
 219 }
 220
 221 static int part_writev(struct mtd_info *mtd, const struct kvec *vecs,
 222                 unsigned long count, loff_t to, size_t *retlen)
 223 {
 224         struct mtd_part *part = mtd_to_part(mtd);
 225         return part->master->_writev(part->master, vecs, count,
 226                                      to + part->offset, retlen);
 227 }
 228
 229 static int part_erase(struct mtd_info *mtd, struct erase_info *instr)
 230 {
 231         struct mtd_part *part = mtd_to_part(mtd);
 232         int ret;
 233
 234         instr->addr += part->offset;
 235         ret = part->master->_erase(part->master, instr);
 236         if (ret) {
 237                 if (instr->fail_addr != MTD_FAIL_ADDR_UNKNOWN)
 238                         instr->fail_addr -= part->offset;
 239                 instr->addr -= part->offset;
 240         }
 241         return ret;
 242 }
 243
 244 void mtd_erase_callback(struct erase_info *instr)
 245 {
 246         if (instr->mtd->_erase == part_erase) {
 247                 struct mtd_part *part = mtd_to_part(instr->mtd);
 248
 249                 if (instr->fail_addr != MTD_FAIL_ADDR_UNKNOWN)
 250                         instr->fail_addr -= part->offset;
 251                 instr->addr -= part->offset;
 252         }
 253         if (instr->callback)
 254                 instr->callback(instr);
 255 }
 256 EXPORT_SYMBOL_GPL(mtd_erase_callback);
 257
 258 static int part_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
 259 {
 260         struct mtd_part *part = mtd_to_part(mtd);
 261         return part->master->_lock(part->master, ofs + part->offset, len);
 262 }
 263
 264 static int part_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
 265 {
 266         struct mtd_part *part = mtd_to_part(mtd);
 267         return part->master->_unlock(part->master, ofs + part->offset, len);
 268 }
 269
 270 static int part_is_locked(struct mtd_info *mtd, loff_t ofs, uint64_t len)
 271 {
 272         struct mtd_part *part = mtd_to_part(mtd);
 273         return part->master->_is_locked(part->master, ofs + part->offset, len);
 274 }
 275
 276 static void part_sync(struct mtd_info *mtd)
 277 {
 278         struct mtd_part *part = mtd_to_part(mtd);
 279         part->master->_sync(part->master);
 280 }
 281
 282 static int part_suspend(struct mtd_info *mtd)
 283 {
 284         struct mtd_part *part = mtd_to_part(mtd);
 285         return part->master->_suspend(part->master);
 286 }
 287
 288 static void part_resume(struct mtd_info *mtd)
 289 {
 290         struct mtd_part *part = mtd_to_part(mtd);
 291         part->master->_resume(part->master);
 292 }
 293
 294 static int part_block_isreserved(struct mtd_info *mtd, loff_t ofs)
 295 {
 296         struct mtd_part *part = mtd_to_part(mtd);
 297         ofs += part->offset;
 298         return part->master->_block_isreserved(part->master, ofs);
 299 }
 300
 301 static int part_block_isbad(struct mtd_info *mtd, loff_t ofs)
 302 {
 303         struct mtd_part *part = mtd_to_part(mtd);
 304         ofs += part->offset;
 305         return part->master->_block_isbad(part->master, ofs);
 306 }
 307
 308 static int part_block_markbad(struct mtd_info *mtd, loff_t ofs)
 309 {
 310         struct mtd_part *part = mtd_to_part(mtd);
 311         int res;
 312
 313         ofs += part->offset;
 314         res = part->master->_block_markbad(part->master, ofs);
 315         if (!res)
 316                 mtd->ecc_stats.badblocks++;
 317         return res;
 318 }
 319
 320 static int part_get_device(struct mtd_info *mtd)
 321 {
 322         struct mtd_part *part = mtd_to_part(mtd);
 323         return part->master->_get_device(part->master);
 324 }
 325
 326 static void part_put_device(struct mtd_info *mtd)
 327 {
 328         struct mtd_part *part = mtd_to_part(mtd);
 329         part->master->_put_device(part->master);
 330 }
 331
 332 static int part_ooblayout_ecc(struct mtd_info *mtd, int section,
 333                               struct mtd_oob_region *oobregion)
 334 {
 335         struct mtd_part *part = mtd_to_part(mtd);
 336
 337         return mtd_ooblayout_ecc(part->master, section, oobregion);
 338 }
 339
 340 static int part_ooblayout_free(struct mtd_info *mtd, int section,
 341                                struct mtd_oob_region *oobregion)
 342 {
 343         struct mtd_part *part = mtd_to_part(mtd);
 344
 345         return mtd_ooblayout_free(part->master, section, oobregion);
 346 }
 347
 348 static const struct mtd_ooblayout_ops part_ooblayout_ops = {
 349         .ecc = part_ooblayout_ecc,
 350         .free = part_ooblayout_free,
 351 };
 352
 353 static inline void free_partition(struct mtd_part *p)
 354 {
 355         kfree(p->mtd.name);
 356         kfree(p);
 357 }
 358
 359 /*
 360  * This function unregisters and destroy all slave MTD objects which are
 361  * attached to the given master MTD object.
 362  */
 363
 364 int del_mtd_partitions(struct mtd_info *master)
 365 {
 366         struct mtd_part *slave, *next;
 367         int ret, err = 0;
 368
 369         mutex_lock(&mtd_partitions_mutex);
 370         list_for_each_entry_safe(slave, next, &mtd_partitions, list)
 371                 if (slave->master == master) {
 372                         ret = del_mtd_device(&slave->mtd);
 373                         if (ret < 0) {
 374                                 err = ret;
 375                                 continue;
 376                         }
 377                         list_del(&slave->list);
 378                         free_partition(slave);
 379                 }
 380         mutex_unlock(&mtd_partitions_mutex);
 381
 382         return err;
 383 }
 384
 385 static struct mtd_part *allocate_partition(struct mtd_info *master,
 386                         const struct mtd_partition *part, int partno,
 387                         uint64_t cur_offset)
 388 {
 389         struct mtd_part *slave;
 390         char *name;
 391
 392         /* allocate the partition structure */
 393         slave = kzalloc(sizeof(*slave), GFP_KERNEL);
 394         name = kstrdup(part->name, GFP_KERNEL);
 395         if (!name || !slave) {
 396                 printk(KERN_ERR"memory allocation error while creating partitions for \"%s\"\n",
 397                        master->name);
 398                 kfree(name);
 399                 kfree(slave);
 400                 return ERR_PTR(-ENOMEM);
 401         }
 402
 403         /* set up the MTD object for this partition */
 404         slave->mtd.type = master->type;
 405         slave->mtd.flags = master->flags & ~part->mask_flags;
 406         slave->mtd.size = part->size;
 407         slave->mtd.writesize = master->writesize;
 408         slave->mtd.writebufsize = master->writebufsize;
 409         slave->mtd.oobsize = master->oobsize;
 410         slave->mtd.oobavail = master->oobavail;
 411         slave->mtd.subpage_sft = master->subpage_sft;
 412         slave->mtd.pairing = master->pairing;
 413
 414         slave->mtd.name = name;
 415         slave->mtd.owner = master->owner;
 416
 417         /* NOTE: Historically, we didn't arrange MTDs as a tree out of
 418          * concern for showing the same data in multiple partitions.
 419          * However, it is very useful to have the master node present,
 420          * so the MTD_PARTITIONED_MASTER option allows that. The master
 421          * will have device nodes etc only if this is set, so make the
 422          * parent conditional on that option. Note, this is a way to
 423          * distinguish between the master and the partition in sysfs.
 424          */
 425         slave->mtd.dev.parent = IS_ENABLED(CONFIG_MTD_PARTITIONED_MASTER) ?
 426                                 &master->dev :
 427                                 master->dev.parent;
 428
 429         slave->mtd._read = part_read;
 430         slave->mtd._write = part_write;
 431
 432         if (master->_panic_write)
 433                 slave->mtd._panic_write = part_panic_write;
 434
 435         if (master->_point && master->_unpoint) {
 436                 slave->mtd._point = part_point;
 437                 slave->mtd._unpoint = part_unpoint;
 438         }
 439
 440         if (master->_get_unmapped_area)
 441                 slave->mtd._get_unmapped_area = part_get_unmapped_area;
 442         if (master->_read_oob)
 443                 slave->mtd._read_oob = part_read_oob;
 444         if (master->_write_oob)
 445                 slave->mtd._write_oob = part_write_oob;
 446         if (master->_read_user_prot_reg)
 447                 slave->mtd._read_user_prot_reg = part_read_user_prot_reg;
 448         if (master->_read_fact_prot_reg)
 449                 slave->mtd._read_fact_prot_reg = part_read_fact_prot_reg;
 450         if (master->_write_user_prot_reg)
 451                 slave->mtd._write_user_prot_reg = part_write_user_prot_reg;
 452         if (master->_lock_user_prot_reg)
 453                 slave->mtd._lock_user_prot_reg = part_lock_user_prot_reg;
 454         if (master->_get_user_prot_info)
 455                 slave->mtd._get_user_prot_info = part_get_user_prot_info;
 456         if (master->_get_fact_prot_info)
 457                 slave->mtd._get_fact_prot_info = part_get_fact_prot_info;
 458         if (master->_sync)
 459                 slave->mtd._sync = part_sync;
 460         if (!partno && !master->dev.class && master->_suspend &&
 461             master->_resume) {
 462                         slave->mtd._suspend = part_suspend;
 463                         slave->mtd._resume = part_resume;
 464         }
 465         if (master->_writev)
 466                 slave->mtd._writev = part_writev;
 467         if (master->_lock)
 468                 slave->mtd._lock = part_lock;
 469         if (master->_unlock)
 470                 slave->mtd._unlock = part_unlock;
 471         if (master->_is_locked)
 472                 slave->mtd._is_locked = part_is_locked;
 473         if (master->_block_isreserved)
 474                 slave->mtd._block_isreserved = part_block_isreserved;
 475         if (master->_block_isbad)
 476                 slave->mtd._block_isbad = part_block_isbad;
 477         if (master->_block_markbad)
 478                 slave->mtd._block_markbad = part_block_markbad;
 479
 480         if (master->_get_device)
 481                 slave->mtd._get_device = part_get_device;
 482         if (master->_put_device)
 483                 slave->mtd._put_device = part_put_device;
 484
 485         slave->mtd._erase = part_erase;
 486         slave->master = master;
 487         slave->offset = part->offset;
 488
 489         if (slave->offset == MTDPART_OFS_APPEND)
 490                 slave->offset = cur_offset;
 491         if (slave->offset == MTDPART_OFS_NXTBLK) {
 492                 slave->offset = cur_offset;
 493                 if (mtd_mod_by_eb(cur_offset, master) != 0) {
 494                         /* Round up to next erasesize */
 495                         slave->offset = (mtd_div_by_eb(cur_offset, master) + 1) * master->erasesize;
 496                         printk(KERN_NOTICE "Moving partition %d: "
 497                                "0x%012llx -> 0x%012llx\n", partno,
 498                                (unsigned long long)cur_offset, (unsigned long long)slave->offset);
 499                 }
 500         }
 501         if (slave->offset == MTDPART_OFS_RETAIN) {
 502                 slave->offset = cur_offset;
 503                 if (master->size - slave->offset >= slave->mtd.size) {
 504                         slave->mtd.size = master->size - slave->offset
 505                                                         - slave->mtd.size;
 506                 } else {
 507                         printk(KERN_ERR "mtd partition \"%s\" doesn't have enough space: %#llx < %#llx, disabled\n",
 508                                 part->name, master->size - slave->offset,
 509                                 slave->mtd.size);
 510                         /* register to preserve ordering */
 511                         goto out_register;
 512                 }
 513         }
 514         if (slave->mtd.size == MTDPART_SIZ_FULL)
 515                 slave->mtd.size = master->size - slave->offset;
 516
 517         printk(KERN_NOTICE "0x%012llx-0x%012llx : \"%s\"\n", (unsigned long long)slave->offset,
 518                 (unsigned long long)(slave->offset + slave->mtd.size), slave->mtd.name);
 519
 520         /* let's do some sanity checks */
 521         if (slave->offset >= master->size) {
 522                 /* let's register it anyway to preserve ordering */
 523                 slave->offset = 0;
 524                 slave->mtd.size = 0;
 525                 printk(KERN_ERR"mtd: partition \"%s\" is out of reach -- disabled\n",
 526                         part->name);
 527                 goto out_register;
 528         }
 529         if (slave->offset + slave->mtd.size > master->size) {
 530                 slave->mtd.size = master->size - slave->offset;
 531                 printk(KERN_WARNING"mtd: partition \"%s\" extends beyond the end of device \"%s\" -- size truncated to %#llx\n",
 532                         part->name, master->name, (unsigned long long)slave->mtd.size);
 533         }
 534         if (master->numeraseregions > 1) {
 535                 /* Deal with variable erase size stuff */
 536                 int i, max = master->numeraseregions;
 537                 u64 end = slave->offset + slave->mtd.size;
 538                 struct mtd_erase_region_info *regions = master->eraseregions;
 539
 540                 /* Find the first erase regions which is part of this
 541                  * partition. */
 542                 for (i = 0; i < max && regions[i].offset <= slave->offset; i++)
 543                         ;
 544                 /* The loop searched for the region _behind_ the first one */
 545                 if (i > 0)
 546                         i--;
 547
 548                 /* Pick biggest erasesize */
 549                 for (; i < max && regions[i].offset < end; i++) {
 550                         if (slave->mtd.erasesize < regions[i].erasesize) {
 551                                 slave->mtd.erasesize = regions[i].erasesize;
 552                         }
 553                 }
 554                 BUG_ON(slave->mtd.erasesize == 0);
 555         } else {
 556                 /* Single erase size */
 557                 slave->mtd.erasesize = master->erasesize;
 558         }
 559
 560         if ((slave->mtd.flags & MTD_WRITEABLE) &&
 561             mtd_mod_by_eb(slave->offset, &slave->mtd)) {
 562                 /* Doesn't start on a boundary of major erase size */
 563                 /* FIXME: Let it be writable if it is on a boundary of
 564                  * _minor_ erase size though */
 565                 slave->mtd.flags &= ~MTD_WRITEABLE;
 566                 printk(KERN_WARNING"mtd: partition \"%s\" doesn't start on an erase block boundary -- force read-only\n",
 567                         part->name);
 568         }
 569         if ((slave->mtd.flags & MTD_WRITEABLE) &&
 570             mtd_mod_by_eb(slave->mtd.size, &slave->mtd)) {
 571                 slave->mtd.flags &= ~MTD_WRITEABLE;
 572                 printk(KERN_WARNING"mtd: partition \"%s\" doesn't end on an erase block -- force read-only\n",
 573                         part->name);
 574         }
 575
 576         mtd_set_ooblayout(&slave->mtd, &part_ooblayout_ops);
 577         slave->mtd.ecc_step_size = master->ecc_step_size;
 578         slave->mtd.ecc_strength = master->ecc_strength;
 579         slave->mtd.bitflip_threshold = master->bitflip_threshold;
 580
 581         if (master->_block_isbad) {
 582                 uint64_t offs = 0;
 583
 584                 while (offs < slave->mtd.size) {
 585                         if (mtd_block_isreserved(master, offs + slave->offset))
 586                                 slave->mtd.ecc_stats.bbtblocks++;
 587                         else if (mtd_block_isbad(master, offs + slave->offset))
 588                                 slave->mtd.ecc_stats.badblocks++;
 589                         offs += slave->mtd.erasesize;
 590                 }
 591         }
 592
 593 out_register:
 594         return slave;
 595 }
 596
 597 static ssize_t mtd_partition_offset_show(struct device *dev,
 598                 struct device_attribute *attr, char *buf)
 599 {
 600         struct mtd_info *mtd = dev_get_drvdata(dev);
 601         struct mtd_part *part = mtd_to_part(mtd);
 602         return snprintf(buf, PAGE_SIZE, "%lld\n", part->offset);
 603 }
 604
 605 static DEVICE_ATTR(offset, S_IRUGO, mtd_partition_offset_show, NULL);
 606
 607 static const struct attribute *mtd_partition_attrs[] = {
 608         &dev_attr_offset.attr,
 609         NULL
 610 };
 611
 612 static int mtd_add_partition_attrs(struct mtd_part *new)
 613 {
 614         int ret = sysfs_create_files(&new->mtd.dev.kobj, mtd_partition_attrs);
 615         if (ret)
 616                 printk(KERN_WARNING
 617                        "mtd: failed to create partition attrs, err=%d\n", ret);
 618         return ret;
 619 }
 620
 621 int mtd_add_partition(struct mtd_info *master, const char *name,
 622                       long long offset, long long length)
 623 {
 624         struct mtd_partition part;
 625         struct mtd_part *new;
 626         int ret = 0;
 627
 628         /* the direct offset is expected */
 629         if (offset == MTDPART_OFS_APPEND ||
 630             offset == MTDPART_OFS_NXTBLK)
 631                 return -EINVAL;
 632
 633         if (length == MTDPART_SIZ_FULL)
 634                 length = master->size - offset;
 635
 636         if (length <= 0)
 637                 return -EINVAL;
 638
 639         memset(&part, 0, sizeof(part));
 640         part.name = name;
 641         part.size = length;
 642         part.offset = offset;
 643
 644         new = allocate_partition(master, &part, -1, offset);
 645         if (IS_ERR(new))
 646                 return PTR_ERR(new);
 647
 648         mutex_lock(&mtd_partitions_mutex);
 649         list_add(&new->list, &mtd_partitions);
 650         mutex_unlock(&mtd_partitions_mutex);
 651
 652         add_mtd_device(&new->mtd);
 653
 654         mtd_add_partition_attrs(new);
 655
 656         return ret;
 657 }
 658 EXPORT_SYMBOL_GPL(mtd_add_partition);
 659
 660 int mtd_del_partition(struct mtd_info *master, int partno)
 661 {
 662         struct mtd_part *slave, *next;
 663         int ret = -EINVAL;
 664
 665         mutex_lock(&mtd_partitions_mutex);
 666         list_for_each_entry_safe(slave, next, &mtd_partitions, list)
 667                 if ((slave->master == master) &&
 668                     (slave->mtd.index == partno)) {
 669                         sysfs_remove_files(&slave->mtd.dev.kobj,
 670                                            mtd_partition_attrs);
 671                         ret = del_mtd_device(&slave->mtd);
 672                         if (ret < 0)
 673                                 break;
 674
 675                         list_del(&slave->list);
 676                         free_partition(slave);
 677                         break;
 678                 }
 679         mutex_unlock(&mtd_partitions_mutex);
 680
 681         return ret;
 682 }
 683 EXPORT_SYMBOL_GPL(mtd_del_partition);
 684
 685 /*
 686  * This function, given a master MTD object and a partition table, creates
 687  * and registers slave MTD objects which are bound to the master according to
 688  * the partition definitions.
 689  *
 690  * For historical reasons, this function's caller only registers the master
 691  * if the MTD_PARTITIONED_MASTER config option is set.
 692  */
 693
 694 int add_mtd_partitions(struct mtd_info *master,
 695                        const struct mtd_partition *parts,
 696                        int nbparts)
 697 {
 698         struct mtd_part *slave;
 699         uint64_t cur_offset = 0;
 700         int i;
 701
 702         printk(KERN_NOTICE "Creating %d MTD partitions on \"%s\":\n", nbparts, master->name);
 703
 704         for (i = 0; i < nbparts; i++) {
 705                 slave = allocate_partition(master, parts + i, i, cur_offset);
 706                 if (IS_ERR(slave)) {
 707                         del_mtd_partitions(master);
 708                         return PTR_ERR(slave);
 709                 }
 710
 711                 mutex_lock(&mtd_partitions_mutex);
 712                 list_add(&slave->list, &mtd_partitions);
 713                 mutex_unlock(&mtd_partitions_mutex);
 714
 715                 add_mtd_device(&slave->mtd);
 716                 mtd_add_partition_attrs(slave);
 717
 718                 cur_offset = slave->offset + slave->mtd.size;
 719         }
 720
 721         return 0;
 722 }
 723
 724 static DEFINE_SPINLOCK(part_parser_lock);
 725 static LIST_HEAD(part_parsers);
 726
 727 static struct mtd_part_parser *mtd_part_parser_get(const char *name)
 728 {
 729         struct mtd_part_parser *p, *ret = NULL;
 730
 731         spin_lock(&part_parser_lock);
 732
 733         list_for_each_entry(p, &part_parsers, list)
 734                 if (!strcmp(p->name, name) && try_module_get(p->owner)) {
 735                         ret = p;
 736                         break;
 737                 }
 738
 739         spin_unlock(&part_parser_lock);
 740
 741         return ret;
 742 }
 743
 744 static inline void mtd_part_parser_put(const struct mtd_part_parser *p)
 745 {
 746         module_put(p->owner);
 747 }
 748
 749 /*
 750  * Many partition parsers just expected the core to kfree() all their data in
 751  * one chunk. Do that by default.
 752  */
 753 static void mtd_part_parser_cleanup_default(const struct mtd_partition *pparts,
 754                                             int nr_parts)
 755 {
 756         kfree(pparts);
 757 }
 758
 759 int __register_mtd_parser(struct mtd_part_parser *p, struct module *owner)
 760 {
 761         p->owner = owner;
 762
 763         if (!p->cleanup)
 764                 p->cleanup = &mtd_part_parser_cleanup_default;
 765
 766         spin_lock(&part_parser_lock);
 767         list_add(&p->list, &part_parsers);
 768         spin_unlock(&part_parser_lock);
 769
 770         return 0;
 771 }
 772 EXPORT_SYMBOL_GPL(__register_mtd_parser);
 773
 774 void deregister_mtd_parser(struct mtd_part_parser *p)
 775 {
 776         spin_lock(&part_parser_lock);
 777         list_del(&p->list);
 778         spin_unlock(&part_parser_lock);
 779 }
 780 EXPORT_SYMBOL_GPL(deregister_mtd_parser);
 781
 782 /*
 783  * Do not forget to update 'parse_mtd_partitions()' kerneldoc comment if you
 784  * are changing this array!
 785  */
 786 static const char * const default_mtd_part_types[] = {
 787         "cmdlinepart",
 788         "ofpart",
 789         NULL
 790 };
 791
 792 /**
 793  * parse_mtd_partitions - parse MTD partitions
 794  * @master: the master partition (describes whole MTD device)
 795  * @types: names of partition parsers to try or %NULL
 796  * @pparts: info about partitions found is returned here
 797  * @data: MTD partition parser-specific data
 798  *
 799  * This function tries to find partition on MTD device @master. It uses MTD
 800  * partition parsers, specified in @types. However, if @types is %NULL, then
 801  * the default list of parsers is used. The default list contains only the
 802  * "cmdlinepart" and "ofpart" parsers ATM.
 803  * Note: If there are more then one parser in @types, the kernel only takes the
 804  * partitions parsed out by the first parser.
 805  *
 806  * This function may return:
 807  * o a negative error code in case of failure
 808  * o zero otherwise, and @pparts will describe the partitions, number of
 809  *   partitions, and the parser which parsed them. Caller must release
 810  *   resources with mtd_part_parser_cleanup() when finished with the returned
 811  *   data.
 812  */
 813 int parse_mtd_partitions(struct mtd_info *master, const char *const *types,
 814                          struct mtd_partitions *pparts,
 815                          struct mtd_part_parser_data *data)
 816 {
 817         struct mtd_part_parser *parser;
 818         int ret, err = 0;
 819
 820         if (!types)
 821                 types = default_mtd_part_types;
 822
 823         for ( ; *types; types++) {
 824                 pr_debug("%s: parsing partitions %s\n", master->name, *types);
 825                 parser = mtd_part_parser_get(*types);
 826                 if (!parser && !request_module("%s", *types))
 827                         parser = mtd_part_parser_get(*types);
 828                 pr_debug("%s: got parser %s\n", master->name,
 829                          parser ? parser->name : NULL);
 830                 if (!parser)
 831                         continue;
 832                 ret = (*parser->parse_fn)(master, &pparts->parts, data);
 833                 pr_debug("%s: parser %s: %i\n",
 834                          master->name, parser->name, ret);
 835                 if (ret > 0) {
 836                         printk(KERN_NOTICE "%d %s partitions found on MTD device %s\n",
 837                                ret, parser->name, master->name);
 838                         pparts->nr_parts = ret;
 839                         pparts->parser = parser;
 840                         return 0;
 841                 }
 842                 mtd_part_parser_put(parser);
 843                 /*
 844                  * Stash the first error we see; only report it if no parser
 845                  * succeeds
 846                  */
 847                 if (ret < 0 && !err)
 848                         err = ret;
 849         }
 850         return err;
 851 }
 852
 853 void mtd_part_parser_cleanup(struct mtd_partitions *parts)
 854 {
 855         const struct mtd_part_parser *parser;
 856
 857         if (!parts)
 858                 return;
 859
 860         parser = parts->parser;
 861         if (parser) {
 862                 if (parser->cleanup)
 863                         parser->cleanup(parts->parts, parts->nr_parts);
 864
 865                 mtd_part_parser_put(parser);
 866         }
 867 }
 868
 869 int mtd_is_partition(const struct mtd_info *mtd)
 870 {
 871         struct mtd_part *part;
 872         int ispart = 0;
 873
 874         mutex_lock(&mtd_partitions_mutex);
 875         list_for_each_entry(part, &mtd_partitions, list)
 876                 if (&part->mtd == mtd) {
 877                         ispart = 1;
 878                         break;
 879                 }
 880         mutex_unlock(&mtd_partitions_mutex);
 881
 882         return ispart;
 883 }
 884 EXPORT_SYMBOL_GPL(mtd_is_partition);
 885
 886 /* Returns the size of the entire flash chip */
 887 uint64_t mtd_get_device_size(const struct mtd_info *mtd)
 888 {
 889         if (!mtd_is_partition(mtd))
 890                 return mtd->size;
 891
 892         return mtd_to_part(mtd)->master->size;
 893 }
 894 EXPORT_SYMBOL_GPL(mtd_get_device_size);